Clamping device for holding cutter-bars for sharpening.



A. B. DONALDSON. CLAMPING DEVIGE FOR HOLDINGOUTTER BARS FOR SHARPENING.

- APPLICATION FILED NOV.19, 1907.

956,31 3, Patnted Apr. 26, 1910.

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ALLEN B. DONALDSON, OF EWING, NEBRASKA.

CLAMPING DEVICE FOR HOLDING CUTTER-BARS FOR SHARPENING.

Specification of Letters Patent.

Patented Apr. 26, 1910.

Application filed November 19, 1907. Serial No. 402,928.

To all whom it may concern:

Be it known that I, ALLEN B. DONALDSON, a citizen of the United States,residing at Ewing, in the county of Holt and State of Nebraska, haveinvented certain new and useful Improvements in Clamping Devices forHolding Cutter-Bars for Sharpening, of-

which the following is a specification.

My invention relates to clamping devices for holding cutter bars forsharpening and its object is to provide a portable stand and clampscarried thereby adapted to securely hold the cutter-bar in place andhaving the clamps so constructed that they maybe readily adjusted to thethickness of the bar, all for the purpose of providing a cutter-barsupporting device which may be readily carried around with the mowingmachine or by hand and set up at any place to enable the cutter to besupported thereon and sharpened by means of a file or other suitablesharpening tool.

To these ends my invention is embodied in preferable form in the devicehereinafter described and illustrated in the accompanying drawings.

In these drawings, Figure 1 is a front view in elevation of the stand;Fig. 2, a top plan view; Fig. 3, a view similar to Fig. 2, showing thecutter bar clamped in place on the stand; Fig. 4c, an enlarged detailend view showing one of the clamps and the cutter bar in clampedposition.

Referring to the drawings, the stand has base-pieces 1, to which aresecured the uprights 2. Diagonally extending brace-pieces 3, join eachupright to its respective basepiece. To these uprights near their upperends is secured a cross-bar 4, the upper surface of which is adapted toform the bed of the connecting bar of the cutter blade sections. Theends of 'the uprights project beyond the surface of the bar 4, to formshoulders 5, of a height substantially equal to the thickness of the barof the cutter. The cutter blade sections rest upon the upper ends of theuprights and between the uprights are additional supporting membersconsisting of metallic bars having vertical arms 6 secured to thecross-bar 4 and rising above said bar to form shoulders corresponding tothe shoulders 5, and then extended outwardly into horizontal fingers 8on which the cutter blade sections bear when the bar is clamped inposition.

Fixed in the cross-bar 4: and extending forwardly and horizontallytherefrom are screws 9, 9, one at each of the cross-bars and oppositethe shoulder of the upright. On these screws are mounted clamps 10,having vertical arms 11, provided with elongated vertical slots 12,which slots fit over the screws. From the upper ends of these arms 11,extend horizontally over the cross-bar, pressure-fingers 13, adapted tobear upon the cutter. A winged nut let, is mounted on each of the screwsand is adapted to firmly secure the clamp in place at any desiredadjustment. By means of the vertical arm of the clamp with the elongatedslot, an extremely simple and effective means of enabling cutter bars ofdifferent thicknesses to be clamped in position is provided, without thenecessity of providing a removable or adjustable supporting bed.

Secured to an intermediate cross-bar 15 is a tool box 16 in which may becarried the sharpening file, extra clamps or other attachments for theclamping stand or the mower.

Extending from the base is a lower crossbar 17 forming a foot restadapted to be employed when the operator is filing the cutter andserving also as a brace for the uprights securing rigidity of the frameof the stand.

A stand so constructed is particularly designed to be carried on themower or by hand around the fields during the hay mowing and isespecially intended to be employed in connection with a file forsharpening the cutter, which I have found to impart a much sharper andmore durable edge than the grindstone and to require less labor andtime.

In the use of my invention, a cutter provided with a connectingcutter-bar 18, for the cutter-sections is placed on the upper ends'ofthe uprights 2, with the bar 18, fitting down on the cross-bar 4 andagainst the shoulders 5 of the uprights and the shoulders 7 of theadditional supporting members. The cutter teeth sections 19, extend overand are supported by the upper ends of the uprights and horizontalfingers 8 of the intermediate supporting members and then the clamps areadjusted into position against the cutter-bar and tightened by means ofthe winged nuts.

Having thus described my invention, What I claim is 1. A stand forholding mower cutters for sharpening comprising base pieces, uprights, across-bar adapted to receive and to support the connecting bar of theblade sections, saic uprights extending above the cross-bar andproviding stop shoulders against which the said connecting bar bears,and intermediate supporting members secured to the cross-bar and havinghorizontal portions to receive the blade sections and also having stopshoulders for the edge of the said connecting bar, substantially asdescribed.

2. In a cutter clamping device, stand having upright legs, a cross-barextending between the same, at the upper part thereof and forming afixed bed for the connecting bar of the cutter sections, said uprightspro jecting above said bar whereby shoulders are provided against whichthe inner edge of the cutter bar is adapted to bear and clamps havingvertical portions eontining the outer edge of the cutter and havingfingers projecting horizontally over said cross-bar, said clamps havingvertically elongated slots whereby the clamps are made adjustable andmeans to secure said clamps in position, substantially as described.

8. In a cutter clamping device, a portable stand having upright legs, across-bar forming a rigid horizontal bed for the connecting bar of thecutter, said uprights projecting above the cross-bar to providecutterbar holding shoulders, horizontal intermediate supporting membershaving vertical shoulder portions adjustable clamp members, havingvertical cutter bar confining portions and horizontal pressure lingersand vertically elongated slots, screws on which the members are mountedand wing-nuts engaging the screws, substantially described.

In testimony whereof l lave attixed my signature, in presence of twowitnesses.

ALLEN B. DONA LDSON.

\Yitnesses J. A. Tuonnnnnsrru;ssnn, V. E. Bunny.

